broken check valve from throttle bodies to map sensor

[Kevin Jones]

A bit more complicated than I thought and it took a while to diagnose the problem as I had a charging problem too. Unexpected and intermittent inability to idle and would only run at half throttle and like ass. I can post pics of plugs too if that tells any story but keep in mind my tuner fattened my low rpm and throttle % map too. Maybe not determinable by plug judging. Anyway, I had broken the special RCC check valve that goes between the map sensor and the throttle bodies. It took me a long time to find this out. It is a special check valve made to bleed boost off and not send an FI warning to the map sensor and it may be a little more than that depending on ecu settings (I think). I called Richard and it would take 2 weeks to get a new one from Canada. I called Rob and he told me go straight to map sensor and yes it would give the FI light. It did. It also didnt run right. It ran, but not well. You cannot simply place an autozone check valve inbetween the two. Face it the wrong way, it wont idle or run. Face it the other way, YMMV depending on your tune but you may not run well. So I googled. I found this. I made this contraption not using 3 check valves but 2. With 7 psi, I think I am ok. Sure there are 50 ways to skin a cat but this is seeming to work for me for now.
Qeustion on check valve to map sensor... - HomemadeTurbo - DIY Turbo Forum

 

[OZBooster]

Yup thats how it should be
Alternative is to flash it , there is a IAP tic box to turn off the warning in editor
(also gives you the opportunity to set hardcut and adjust rpm limits if wanted)

 

[Kevin Jones]

The tuner that did my tune, I wont mention his name, lost my .bin file. And cannot recreate it. This baffles me. In fact in my critical thinking mind, I do not believe it. Therefore, I cannot touch my ecu. He did all the fuel tuning with a pc5. I thought sensibly he would have just wiped the fuel on the ecu and done all of that via power commander and only used the ecu for everything minus fuel but I see fuel cut on early throttle % and low rpm which means I dont think he did. Actually, he may not know what he did. He did spend 3 hours on the dyno and built the pc map completely from another map that wasnt even close. Truth is, I dont know wtf he did and I dont think he does either. I begged and begged for him to take a GUESS and build an ecu map. He wont.

 

[OZBooster]

Ok that sucks,

check valve is a sound plan untill you want to do other ecu related stuff, then check your tune after flashing a new base setup
he probably made very little fuel change if the pcv was planned, but may have pulled some timing or reset limiters etc